Submitted by Larry Jankowski, CBDT
A 58 year old white female, natural menopause at age 48, 68 inches tall (no reported height loss from age 25), 132 lbs (BMI=20.1), with a medical history unremarkable except for a 5 year history of pseudogout with no acute symtoms at this time, and recent stress fractures of her right 4th and 5th metacarpal bones, prompting a repeat DXA despite several previous scans showing stable osteoporosis based on a lowest T-score of -2.5 at the spine. She declined treatment because she had no other osteoporosis risk factors and most recent FRAX results of 7.6% major, and 1.0% 10 year fracture risks. She was referred to a rheumatologist as the study revealed a 11.4% loss of BMD at the left femur neck in 14 months with no statistically significant losses seen at the spine or total hip and her PCP was concerned of possible secondary causes.
The images and BMD values for the prior and current hip and spine scans are shown below.
- Are the spine and hip scans comparable and does this represent a true loss in BMD at the femur neck? (LSC at this facility is reported to be 0.026 g/cm2 at the spine, 0.024 g/cm2 at the total hip, and 0.036 g/cm2 at the femur neck.)
- What is the most likely cause for the measured loss in BMD at only the femur neck in this patient?
- What recommendations, in terms of additional work-up, would be appropriate on the basis of these scans?